Missing two key big men in its deep rotation and saddled with an unexpected Del Rey League loss without its longtime coach on the sidelines, it hasn’t been the best week for the Serra boys basketball team.

With only eight games total in the five-team league, the Cavaliers could ill afford to fall further in the standings. To avoid that meant having to find a way to get past Bishop Montgomery, the Del Rey’s other chief title contender.

Serra showed some grit and did the dirty work Friday night on its home court, grinding out a much-needed 58-55 victory in a defensive struggle between two of the South Bay’s best programs.

How meaningful was the game to the Cavaliers? Shooting guard Craig Carter said, “It would hurt us in the standings and it would hurt us in our heart. This is our rival; they’ve been our rival for years. We don’t want to lose to them on our home court.”

The Cavaliers (16-6, 2-1) were coming off a loss to first-place Cathedral on Wednesday in which they managed just 35 points. They played without center Kevin Johnson and forward Leon Gibson, both of whom are out indefinitely because of disciplinary reasons, according to the coaching staff.

Serra coach Dwan Hurt did not disclose a specific nature of the discipline or the reason but indicated that he hopes the two can return before the end of the regular season, pending a school review.

The coach himself wasn’t at Cathedral, having spent the night with his wife for the delivery of their son.

Meanwhile, Bishop Montgomery (18-3, 2-1) was upbeat and focused on putting Serra in a deep hole after easily handling St. Bernard.

Simply put, Hurt said his team couldn’t afford another loss.

“I told the team exactly that,” Hurt said. “A loss today and we would be in a deeper hole than we are. We got ourselves in a deep hole losing to Cathedral so we’ve got to come out here and be very competitive against Bishop Montgomery.”

The Cavaliers played tough pressure defense throughout, forcing 15 turnovers and making Montgomery and its star Justin Cobbs work for nearly everything. It was enough to overcome their offensive issues – 20 turnovers and just one field goal in the fourth quarter.

Survival was the theme. Serra never trailed after the first quarter but nearly lost all of its 10-point lead entering the final period. Still, it managed to withstand every attempt by the Knights to steal a win.

After Chris Miller drained a 3-pointer to cut the lead to 55-53, Montgomery missed on its next four shots with a chance to tie the game or take the lead.

Serra’s Antonio Galaya, who had 12 points, was a factor late as he forced Brandon Bibbins into losing the ball out of the bounds on a drive with 31 seconds left.

Carter made two key free throws with 21.1 seconds left for a 57-53 lead.

“That’s what practice is about,” he said. “You practice them every day. Practice makes perfect. I just went up to the line and was able to knock them down.”

Cobbs made a free throw with 11.8 seconds left, but he worked for his game-high 21 points, making just three field goals and missing seven of his 20 foul shots.

Terran Moore’s 3-point attempt with 3.8 seconds left was blocked by Carter but he was whistled for the foul. Moore made the first try but missed the second, necessitating an intentional miss on the third shot.